Electronic chips such as the chips of bank cards contain confidential data liable to be coveted by pirates. To obtain these data, a pirate may carry out an attack by scanning the back face of the chip with laser pulses. The impact of the laser disrupts the operation of the chip, and the pirate carries out his attack by observing the consequences of these disturbances, called faults, on the activity of the circuits of the chip. To disrupt the operation of the chip, the pirate may also apply high positive or negative potentials, typically of a few tens of volts, for example of more than 50 V, by, for example, using a probe placed in contact with the back face.